It is important to remove contaminants from raw and/or waste waters before discharge of such waters, because contaminants such as those found in sewage waters, various industrial waste waters, storm sewer waters and the like, have a destructive effect on the environment. Existing processes for removing such contaminants from waste waters entail breaking down the biodegradable contaminants by the action of active micro-organisms and removing other contaminants by physical and/or chemical processes. With such processes, several different process steps are carried out in separate stages of a treatment system requiring relatively expensive equipment and the use of substantial areas of land. These types of treatment are complex, have inherent inefficencies and are not readily scaled down for use in treating small volumes of waste waters at a site of limited size.
It has been proposed to use particulate matter in sewage treatment systems. The particulate matter such as activated carbon, flyash, coal, volcanic cinders and calcium carbonate function as adsorbants to adsorb suspended solids in the waste waters and thereby remove such suspended solids from the waste waters. The waste sludge containing the particulate matter, may be discarded or processed to recover the particulate matter from the waste sludge for a return to the system. None of the past proposals have contemplated the use in a sewage treatment system operating at pH range of 6 to 8 of a finely divided mineral or combination of minerals. Such selected minerals must be capable through dissociation, of releasing metal ions which precipitate phosphates in the waste waters simultaneously with the biological reactions to achieve the simultaneous removal of bio-degradable suspended and dissolved organic solids, nitrogenous compounds and phosphates within a single reaction system.
It is therefore an object of the invention to provide a process for removing contaminants from the contaminated waters with a minimum number of process steps.
It is another object of the invention to provide a waste treatment process where various organic suspended solids, nitrogen containing compounds, and phosphorous containing compounds are removed from the waste waters by co-acting and simultaneously occuring biological and chemical reactions.
It is yet another object of the invention to provide a process for purifying contaminated waters, which is capable of unattended operation and readily lends itself to use in large municipal waste water treatment systems, apartment size waste water treatment systems, single family dwelling waste water treatment systems, waste treatment systems on boats, ships, recreational vehicles and the like, in shopping centres, airports, recreational areas, such as camps, waste treatment systems in food processing industries, fish hatcheries, pulp and paper industries, coke processing stages of steel mills, paint industry, and in any other type of industry, domestic area or raw water purification wherein partially or wholly bio-degradable contaminants and certain non-bio-degradable contaminants are to be removed.
It is a further object of the invention to provide a purifying process for waste water where compared to existing systems the waste water may be processed in a more efficient manner to thereby reduce the physical size of a treatment system.